Japanese Patent Publication No. 2004-20787 discloses a microphone device equipped with a microphone formed with a roughly cylindrical outer perimeter surface shape and a rubber holder surrounding the microphone in a cylindrical shape and supporting it. In this microphone, a main microphone unit is held in a roughly cylindrical metal case. The case itself serves as a ground terminal, and a positive terminal is disposed on the bottom end surface of the main microphone unit. The holder is equipped with a bottom wall that extends from the bottom end of the holder to the bottom end surface of the microphone. At least a section of the outer perimeter edge of the bottom wall is formed from a conductive rubber and serves as a first conductive section that is continuous with the ground terminal. A predetermined position away from, and inward of, the first conductive section is formed from conductive rubber and serves as a second conductive section continuous with the positive terminal.
The microphone is aligned and secured in a case of the device it is to be attached to, e.g., a portable telephone, and the bottom surface can be abutted to an external substrate. This will result in the microphone's case, which is the ground terminal, being electrically connected to a ground terminal formed on the external substrate by way of the first conductive section formed on the outer perimeter edge of the bottom wall of the holder, and the positive terminal of the microphone being electrically connected to a positive-side terminal formed on the external substrate by way of the second conductive section.
Thus, the positive terminal of the microphone is connected to corresponding terminals on the external substrate. However, adequate contact force and contact stroke cannot be provided between the plus terminal and the like of the microphone and the conductor sections of the holder. Furthermore, when there is electrical contact with the external substrate, positional relationships are defined, making it difficult to handle different types of microphone arrangements.
Japanese Patent Publication No. 2002-094530 discloses a microphone mounted on a boss in a mobile communication terminal. On one surface of a printed circuit substrate, a circular ring-shaped first contact and a second contact at the center thereof serve as a conductor section. On one surface of the microphone, a circular ring-shaped third contact and a fourth contact at the center thereof serve as a conductor section.
The microphone is inserted into a holder formed from a rubber material in a cylindrical shape and is then mounted on the boss disposed on the lower section surface of the mobile communication terminal case. The lower section surface of the holder is formed with a circular opening that allows the user's voice to be sent to the inserted microphone. On the upper surface thereof, a circular ring-shaped fifth contact and a sixth contact at the center thereof serve as a connector formed in a co-planar manner, thus allowing an electrical connection to be formed between the printed circuit substrate and the microphone.
A cushion is disposed around the fifth and sixth contact so that when the rear case is sealed, shock absorption is provided and the connection between the first and second contacts and the fifth and sixth contacts are guided.
This microphone connection structure is essentially the same as the microphone device from JP '807. The structure can be used in the same manner, provides the same advantages, and solves the same problems.
Japanese Patent Publication No. 2002-152874 discloses an electro-acoustic converter equipped with a microphone, a holder with a cover member that is mounted on the microphone, and a connector that electrically connects the microphone to the external substrate.
The connector is formed from a torsion coil spring that is conductive, and includes an inner end side that abuts a conductor section of the microphone, and an outer end side that abuts a conductor of an external substrate, which corresponds to the conductor of the microphone. The connector includes a shaft-shaped support member that supports the torsion coil spring so that the inner end side abuts the conductor section of the microphone.
This electro-acoustic converter has a conductor on an external substrate that abuts the outer end side of the torsion coil spring forming the connector. However, attaching the torsion coil spring to the shaft-shaped support member is not easy. A cut-out needs to be formed on the shaft-shaped support member, and the coil section has to be fitted to the outside of the shaft-shaped support member using this cut-out. This is a narrow structure and forming a cut-out large enough to allow easy fitting of the coil is difficult. Also, by forming this type of cut-out, the shaft-shaped support member will be supported in a T-shaped arrangement, or, if by the holder, in a cantilevered support. This makes it questionable whether adequate strength can be provided.
Japanese Patent Publication No. 2003-037884 discloses a microphone that includes a support member which supports a microphone on a predetermined support surface. The microphone is formed as a cylindrical case with a sound opening on a ceiling, signal output electrodes on a base and a terminal member, secured to the support member, that transmits a signal from the signal output electrodes to an external circuit. An opening formed on the support surface of the support member is sealed by the terminal member. With this microphone holder, the terminal member is disposed integrally, and the opening created when shaping the support member is sealed by the terminal member. As a result, expansion of the base side of the microphone holder resulting from using sealing means is avoided, thus providing a more compact design.